We have tested the smaller Barton vs the smaller Indy on a 484 Hemi, and both ran very close...The smaller Indy we did have a 1" spacer on it. Plugs from either looked great...The weight difference between them was unreal though...

I have not tested the 4500's against each other. Its taken me a while just to get my junk to run. I hope to enjoy it a little more this year.

'70 Cuda,...605 EFI Hemi Street Car (6.20 best pass, 1.33 60ft)
https://www.youtube.com/watch?v=WYw6RA-k5Bk (6.25 at 108.75mph from inside car)
https://www.youtube.com/watch?v=3zQEb9uxFng (6.25 at 108mph from outside car)
https://www.youtube.com/watch?v=JCvfzsC4NgM (9.9)

'66 Barracuda AWB Stretched nose Blown 440 Car in build stage

'71 Duster Drag Car 400 Low Deck 512 best 6.002 at 115.44mph
https://www.youtube.com/watch?v=Znuo3jMUXTk